/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.io;

import java.io.IOException;
import java.util.zip.*;

/**
 * This DataEntryReader lets a given DataEntryReader read all data entries of the read jar/war/zip data entries.
 *
 * @author Eric Lafortune
 */
public class JarReader implements DataEntryReader {
    private final DataEntryReader dataEntryReader;
    private final boolean jmod;

    /**
     * Creates a new JarReader that doesn't read jmods.
     */
    public JarReader(DataEntryReader dataEntryReader) {
        this(dataEntryReader, false);
    }

    /**
     * Creates a new JarReader.
     */
    public JarReader(DataEntryReader dataEntryReader, boolean jmod) {
        this.dataEntryReader = dataEntryReader;
        this.jmod = jmod;
    }

    // Implementation for DataEntryReader.

    public void read(DataEntry dataEntry) throws IOException {
        if (jmod) {
            // Eat the magic bytes
            dataEntry.getInputStream().read(new byte[4]);
        }

        ZipInputStream zipInputStream = new ZipInputStream(dataEntry.getInputStream());

        try {
            // Get all entries from the input jar.
            while (true) {
                // Can we get another entry?
                ZipEntry zipEntry = zipInputStream.getNextEntry();
                if (zipEntry == null) {
                    break;
                }

                // Delegate the actual reading to the data entry reader.
                dataEntryReader.read(new ZipDataEntry(dataEntry, zipEntry, zipInputStream));
            }
        } finally {
            dataEntry.closeInputStream();
        }
    }
}
